Street-car air-brake



(No Model.)

0. A. GRAY.

STREET GAR AIR BRAKE.

No. 599,421. Patented Feb. 22, 1898.

UNITED STATES PATENT CHARLES A. GRAY, OF KANSAS CITY, KANSAS.

STREET-CAR AIR-BRAKE.

SPECIFICATION forming part of Letters Patent No. 599,421, dated February 22, 1898.. Application filed August 13, 1897. Serial No. 648,170. (No model.)

.To all whom it may concern.-

Be it known that I, CHARLES A. GRAY, a citizen of the United States, residing at Kansas City, in the county of Wyandott-e and State of Kansas, have invented certain new and useful Improvements in Street-Car Air- Brakes; and I do hereby declare that the fol lowing is a full, clear, and exact description of the invention, such as will enable others to make and use the same, reference being had to the accompanying drawings, forming a part of this specification.

My invention has for its object an air-brake operated by compressed air and in which the pressure of the air upon the brake may be instantaneously applied.

In my invention I aim to apply the power to the brake-rod to throw the brake either upon or from the wheels with the same velocity.

Myinvention consistsin the novel construction and combination of parts, such as will first be fully described, and specifically pointed out in the claims.

In the drawings, Figure 1 is a plan view showing the car wheels and axle of an ordinary street-car, the separate brake beams and the shoes upon each beam, and the improved apparatus for operating the brake-beams, the brake-cylinder and compressed-air pump being shown in horizontal section. Fig. 2 is a detail view in perspective of the combined brake-cylinder and Valve-box, showing one of the end plates or heads removed. Fig. 3 is a view of a broken portion of the end of the car-platform, showing the vertical brakeoperating cran k-rod on the platform and aportion of the valve-operating rod to the brakecylinder. Fig. 4 is a detail view of the double cranks connected with the eccentric on the car-axle and also with the piston-rod to the air-compressor, showing the ball or socket joints, also showing one of the car-axles in section and the eccentric and eccentric-rod.

Similar letters of reference indicate corresponding parts in all the figures.

Referring to the drawings, A and A represent the front and rear axles, respectively, of a street-car.

B and B are the wheels on the axle A, and B 13 are the wheels on the axle A.

C represents the brake-beam to the Wheels 13 B' and O the brake-beam to the wheels B B.

ccrepresents the brake-shoes on each brake beam.

0 c are the ordinarysprings on the brake beams connected with the body of the car for throwing. the brake-beams from the wheels.

D represents a compressed-air storage-tank arranged in position between the respective wheels B B and which is connected with the body of the car (not shown) in any well-known manner.

E represents an air compressor or pump which is arranged in position upon the inner side and a short distance from the compressedair tank D, and is also secured to the body of the car and about the same horizontal plane as described of the said tank D.

e is the piston, and e the piston-rod, of the compressor E.

Upon the car-axle A is an eccentric F, around which is a collar f. Vith the collar f is connected one end of an eccentric-rod f. WVith the body of the car is connected a shaft G by means of the brackets g g, upon one end of which shaft is a crank g, which extends in a downward direction, and upon the other end is a crank which extends in an upward direction, said shaft being arranged in position about midway from the cylinder E and the eccentric F. Upon the outer end of the crank g is a socket g and upon the end of the eccentric-rod f is a ball f which fits within the socket 9 Upon the outer end of crank g is a ball 9 Upon the outer end of the piston-rod e is a forked portion 6 in which is pivoted one end of a short fiat bar 6 Upon the other end of bar 2 is a socket e, which receives the ball g on the end of crank 9 In the air-compressing cylinder E at each end is an induction-valve e for the admission of air. With one of the eduction-openings of cylinder E is connected one end of an air-conducting pipe d, the other end of which pipe is connected with the other eductionopening to said cylinder. In the pipe d at each end is a check-valve 6 With the pipe cl is connected one end of an air-conducting pipe d, the other end being connected with the tank D. Within the pipe d is a checkvalve d which prevents the backflow of the air through pipe (2.

In the direction of the car-Wheels B 13 and within the line described by said wheels is a reversing-brake cylinder H, upon one side of which is combined a longitudinal valve box or chamber H. Said cylinder H and valvebox are connected rigidly with the body of the car, as described of the tank D and in about the same horizontal plane. At each end of said cylinder and valve-box is a removable head h, the cylinder H being made air-tight thereby. Through the valve-chamber h extends a valve-operating rod M, which. also passes through both heads or plates h of the combined cylinder and valve-box and extends through the opening 71 in .said heads and a short distance beyond the outside portion of said heads, which opening h is slightly larger than said rod. Upon the rod 72 are separate valves its 72. which are arranged a considerable distance apart for the purposes hereinafter described.

In the combined'portions of the sides of the brake-cylinder H and valve box or chamber h, which is of considerable thickness, as at h, is a passage 7?, which extends from a point near the inner side of the head h of the cylinder H at one end of the cylinder, thence is extended within the portion 7t at an angle to said cylinder in the direction of the other end of said cylinder H and extends within the valve-chamber 72, within a short distance of a point equidistant from the opposite ends of said cylinder H. Near the cylinder-head at the other end of cylinder H is a passage 71 which extends through the portion 71 and into the valve box or chamber h at the same described distance from the point equidistant from the opposite ends of cylinder H, as described of the passage 77/5. The normal position of the valve 7L on the rod 7L2 is upon 'the side of the'passage 71 toward the adjacent head h of the cylinder H and the valve k on the side of the passage h, adjacent to the head h of said cylinder.

With the tank D is connected one end of a supply-pipe, the other end of which pipe is connected with the valve box or chamber h at a point equidistant from the opposite ends of said chamber and also intermediate in position to the passages h 71 Upon the tank D is a pressure-regulating valve R.

In the chamber of the brake-cylinder H is a piston W, with which is connected one end of a piston-rod h On the brake-beam O, at a point equidistant from its opposite end, is an eyebolt is, with which is connected pivotally one end of a rod K. With the body of the car is pivotally connected, by means of the connection or strap Z, the lever L, the position of which lever is within a vertical plane drawn through the axle A and nearly equidistant from said plane and the brake-cylinder I{ With one end of the lever L on one side of the strap 1 is connected the opposite end of the rod to that connected with the brake-beam 0. Upon the other side of the strap Z and with said lever L at a point equidistant from the ends of said. lever is pivotally connected one end of a rod M, the other end of which rod is pivotally connected with an eyebolt 0 on the brake-beam C, said lever L and rods K M being the usual brake devices in common use. With the other forked end of lever L, which is opposite the brakecylinder H, is pivotally connected the pistonrod 72.".

The outer end portion of the valve-rod 71 in the valve-box h is forked, as at h and with said forked portion is pivotally connected one end of branch rod N, the other end of which rod extends to a position beneath the forward end of the platform of the car, as represented more in detail in Fig. 3, in which 0 represents the end portion of the platform of the car, through which passes the operating crank-rod P, upon the upper end of which is a wheel 19 and upon the lower end a crank 19, with which crank is pivotally connected the other end of the rod N from that connected with the valve-rod 72, WVith the other end of the rod h is pivotally connected one end of a rod N, the other end of which rod extends in the direction of the other end of the car and is connected pivotally with a crank upon an operating-rod N, which is precisely the same as the rod P.

In the operation of the invention the movement or rotation of the car-axle A actuates the eccentric F, which in turn operates the compressed-air pump E, the air being alternately drawn within the cylinder of the pump and forced within the pipe d during the forward-and-backward movement of the piston e,.which air enters the tank D and is prevented from returning in the pipe din the check-valve d within the said pipe.

The compressed air in tank D passes outwardly from the said tank through a pipe into the valve-chamber p, thence through the passages h 7L7 into the brake-cylinder H, and bears with equal pressure on both sides of the piston h As seen in Fig. 1, the piston 7L8 is near the rear end of the brake-cylinder and the brake beams and shoes thrown outwardly from the car-wheels. WVhen it is necessary to apply the brake beams and shoes to the car-wheels, the rod Pis turned slightly, which throws the valve-rod h in the direction of the brake-beam O, forcing the valve 77. past the end of the passage 7L and the air from one side of the piston 72, escapes from the valveboX around the valve-rod 71 while the .com pressed air upon the other side of the piston exerts the pressure thereon which is confined in the tank D, and the brake-beams C O are thrown by the action of the piston-rod h on the lever L and the brake is applied suddenly to the car-wheels and the movement of the car arrested. A reverse movement of the red I? throws the valves h 111130 the normal position, as seen in Fig. 1, the equal pressure of the compressed air being restored between said valves and the brake-beams thrown away from the car-wheels. It will therefore be observed that the brake is within the control of the operator to check instantly the movement of the carwheels and to utilize a stored power of great capacity at the instant the brake is required, the prolonged action of the brakeshoesupon the car-wheels being attained by the retention of either valve h h in the position as described between the passages h M. Should the area of pressure on one side of the piston 71. in the brake-cylinder be affected by the displacement of the piston-rod, the springs c c on the brake-beams will overcome the tendency of the piston h to move independently of the action of the valves h h WVhen the brake is not employed, the excess of the compressed air above a defined pressure upon the tank D is permitted to escape through the pressure-regulating valve R.

The obvious value of my improved brake is the facility with which the brake may be applied and thrown off and the action repeated, with slight effort, in turning the rod P, the alternate movement being capable of great speed, thereby checking the speed of the car in degrees within a definite space without coming to a full stop.

I am aware that the action of the brakecylinder has heretofore been caused by a slidevalve connected directly with the compressedair reservoir, with the opposite ends of which slide-valve two separate pipes are connected, and also with the brake-cylinder at opposite ends. In this construction the pressure of the compressed air is only upon one side of the piston in the brake-cylinder at any one time, whereas in my invention the pressure is upon both sides when the brake is not applied, so that in the movement of the valves in the valve-chamber to change the position of the brake the air is not Wholly exhausted from either side of the piston in the brakecylinder and the action of the brake is instantaneous.

Having fully described my invention, what I now claim as new, and desire to secure by Letters Patent, is-- 1. In air-brakes for cars, a compressed-air apparatus comprisinga storage-tank for compressed air, an air-pump and a conductor for compressed air connected with said pump and said tank, means for operating said pump, and a brake-cylinder having heads, a piston and piston-rod in said cylinder, and a valvebox upon said cylinder, having separate inclined passages for the air, each passage extending from the brake-cylinder near the head thereof within the central portion of the valve-box, a valve-rod and separate valves on said rod, each normally in position between one of the passages for the air and the cylinder-head,and a conductor of compressed air connected with said tank for compressed air and also with the valve-box, at a point between the separate valves, and means for operating said valve-carrying rod, as and for the purpose described.

2. The combination with the wheels and axle of a car, of an eccentric upon said caraxle, and an eccentric-rod, a compressed-air pump, a piston and piston-rod in said pump, a shaft between said pump and said car-axle and cranks upon the opposite ends of said shaft, extending in opposite directions, a ball upon the end of said eccentric-rod and said piston-rod, and a socket upon the end of said cranks adapted to receive said ball, as and for the purpose described.

3. The combination with the separate axles of a car, of a wheel-brake lever, separate brake-beams and rods connected with said beams and said lever, a brake-cylinder having heads, a valve-box upon said cylinder,

having separate oblique passages for the air, each passage extending from the brake-cylinder near the head thereof, within the intermediate portion of the valve-box, a piston and piston-rod within said brake-cylinder connected with the outer end portion of the wheel-brake lever, and a valve-rod and separate valves upon said rod within the valvebox, each valve being normally in position between one of the passages for the air and the cylinder-head, a storage-tank for the compressed air having a pressure regulating valve, and a conductor of compressed air connected with said storage-tank and also with the said valve-box, an air-pump, a piston and piston-rod on said pump, a conductor of compressed air connected with said tank and also with said air-pump, an eccentric-on said caraxle, an eccentric-rod, a shaft between said pump and car-axle, and a crank on the opposite ends of said shaft, each extending in opposite directions to the other, and a socket upon said crank, a ball upon said crank, a ball upon the ends of said eccentric-rod, and said piston-rod to said pump adapted to fit the respective sockets upon the said cranks, and means for operating the said valve-rods, substantially as and for the purpose described.

CHARLES A. GRAY. Witnesses:

W. O. THOMAS, A. L. GREEK. 

